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1990

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Wood Specific Gravity Gradients In Tropical Trees., Michael Carl Wiemann Jan 1990

Wood Specific Gravity Gradients In Tropical Trees., Michael Carl Wiemann

LSU Historical Dissertations and Theses

Pith to bark wood specific gravity (SG) trends were measured in tropical trees and compared with trends found in temperate trees. Extraordinary increases were found across the stems of some tropical wet forest colonizing species, with most tropical species showing at least moderate increases. In contrast, temperate species showed little change, and decreases were almost as common as increases. In Chapter One (published in Wood Fiber Sci. 20(3):344-349), three colonizing species in tropical wet forest were found to produce low SG wood when small and to linearly increase SG with diameter growth. Trends in small trees were similar to those …

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Molecular Cloning And Characterization Of The Rhodobacter Capsulatushema Gene., Maureen Smith Wright Jan 1990

Molecular Cloning And Characterization Of The Rhodobacter Capsulatushema Gene., Maureen Smith Wright

LSU Historical Dissertations and Theses

The first step in the common tetrapyrrole pathway in Rhodobacter capsulatus is the condensation of glycine with succinyl CoA to form 5-aminolevulinate which is then used in the synthesis of bacteriochlorophyll, heme, vitamin B-12, and siroheme. To isolate mutants unable to form 5-aminolevulinate, as a first step in studying regulation of the tetrapyrrole pathway, R. capsulatus was mated with E. coli carrying plasmid pSUP2021. pSUP2021 carries transposon Tn5 and is incapable of replicating in R. capsulatus making it an ideal vector for transposon mutagenesis. One colony was found which requires 5-aminolevulinate for growth. This mutant strain, designated AJB529, has a …

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Sugarcane Pollen Viability And Seed Setting As Affected By Daylength Decline Rates And Relative Humidity., Adel Mostafa Abou-Salama Jan 1990

Sugarcane Pollen Viability And Seed Setting As Affected By Daylength Decline Rates And Relative Humidity., Adel Mostafa Abou-Salama

LSU Historical Dissertations and Theses

The effects of daylength decline rates and relative humidity levels and durations on pollen viability and seed setting of sugarcane (Saccharum spp.) were investigated. Two studies were carried out at St. Gabriel Research Station of the Louisiana Agricultural Experiment Station. Daylength decline rates of one half and one minute per day were studied on 354 crosses made within three years using 54 males and 92 females. Males treated with one half minute daylength decline rate had higher pollen viability. Seed production was not affected by the treatments. Varietal differences were found responsible for most of the variation obtained. The two …

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Parametric Motion Transducer For Gravitational Wave Detectors., Odylio Denys De Aguiar Jan 1990

Parametric Motion Transducer For Gravitational Wave Detectors., Odylio Denys De Aguiar

LSU Historical Dissertations and Theses

We designed, constructed, and tested (using two different low phase noise electrical pump generators) a cryogenic double-resonant parabridge motion transducer made out of niobium, whose electrical output was amplified by a two stage MESFET cryogenic amplifier. Most of the experimental results agreed well with the theoretical models, and we successfully measured the mechanical Brownian motion of this transducer. We were able to adjust the two electrical bridge resonant frequencies on top of each other at the pump frequency, allowing us to obtain an electromechanical coupling as high as 0.054. This high coupling, corresponding to an rms electric field strength of …

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Characterization Of Solid Matrices For Solidification/Stabilization Of Hazardous Wastes Using Solid State Nuclear Magnetic Resonance Spectroscopy And Other Analytical Techniques., Humayoun Akhter Jan 1990

Characterization Of Solid Matrices For Solidification/Stabilization Of Hazardous Wastes Using Solid State Nuclear Magnetic Resonance Spectroscopy And Other Analytical Techniques., Humayoun Akhter

LSU Historical Dissertations and Theses

Solidification/stabilization (S/S) is a valuable technology for the treatment of certain waste streams, e.g., metal plating wastes, incinerator ashes, etc., and has great potential for use in treatment of contaminated soils. Although this technology is relatively cheap, significant questions remain about the range of its applicability. Cement chemistry is very complex and poorly understood, and the possibility that contaminants could adversely affect the durability and permeability of the matrix is very real. The broad aims of the present studies are to survey S/S binding agents and additives with respect to their abilities to immobilize As, Cr, Pb, and phenols, the …

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Brugia Pahangi: Effects Of Maternal Filariasis On The Responses Of Their Progeny To Homologous Infection., Stephen Carl Bosshardt Jan 1990

Brugia Pahangi: Effects Of Maternal Filariasis On The Responses Of Their Progeny To Homologous Infection., Stephen Carl Bosshardt

LSU Historical Dissertations and Theses

The effects of in utero and neonatal exposure to maternal Brugia pahangi infections on the development of homologous infections, immune responses, and pathologic lesions was studied in age-matched progeny of infected and uninfected female jirds. High IgG antibody titers to B. pahangi antigens were present in the sera of progeny from infected mothers. These neonatal titers to homologous antigens were shown to be of maternal origin, and did not alter the cellular responses of uninfected progeny as measured by in vitro antigen-stimulated blastogenesis and in vivo pulmonary granulomatous inflammatory responses to antigen-coated beads. Studies were conducted to measure age-related differences …

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Synthesis Of Cyclopentadienyl Derivatives: Stereoelectronic Effects In The Diels-Alder Cyclocondensation Reaction., Jose Gabriel Garcia Jan 1990

Synthesis Of Cyclopentadienyl Derivatives: Stereoelectronic Effects In The Diels-Alder Cyclocondensation Reaction., Jose Gabriel Garcia

LSU Historical Dissertations and Theses

This dissertation is divided into three chapters. Chapter one describes attempts to synthesize bis-monosubstituted cyclopentadienyl compounds as probes for complexation to transition metals. Prior to the attempted synthesis of bis-monosubstituted cyclopentadienyl compounds, the syntheses of two different organic frameworks bearing a C$\sb2$-symmetry axis is described; namely, the 1,3-dioxolane-2,2-dimethyl and the 1,1$\sp\prime$-binaphthyl frameworks. Chapter two describes the attempts to synthesize monofulvene derivatives as model compounds for the synthesis of difulvenes. Also, chapter two describes the attempts to synthesize different difulvene derivatives, that for the most part bear a C$\sb2$-symmetry axis, as model compounds for cyclopentadienyl-derivative anions to be completed to transition …

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Studies In The Electrochemistry Of Insulators And Ion Transport: Anodization, Oscillometry, Electro-Osmosis, And Capillary Electrophoresis., Kiumars Ghowsi Jan 1990

Studies In The Electrochemistry Of Insulators And Ion Transport: Anodization, Oscillometry, Electro-Osmosis, And Capillary Electrophoresis., Kiumars Ghowsi

LSU Historical Dissertations and Theses

In part one, an analytical model for the growth kinetics of the anodic oxidation of Si at constant voltage is developed. The theoretical model derived for the film growth rate is consistent with the existing empirical relation reported earlier. Electronic current density, the major total current component, is shown to be nonohmic and space charge limited. Equations are derived, each as a function of time, for the total current density, the electronic current density, and the ionic efficiency during anodic oxidation. These theoretical predictions are in good agreement with the available experimental data. In part two, the high frequency conductances …

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A Study Of Musical And Extra-Musical Imagery In Rachmaninoff's "Etudes-Tableaux", Opus 39., Raymond J. Gitz Jan 1990

A Study Of Musical And Extra-Musical Imagery In Rachmaninoff's "Etudes-Tableaux", Opus 39., Raymond J. Gitz

LSU Historical Dissertations and Theses

The nine Etudes-Tableaux, op. 39 (1916-17) for piano solo are the last important works written by Sergei Rachmaninoff (1873-1943) before his exile from Russia in 1917. The use of the word "Tableaux" in the title suggests an association with pictures, paintings, or scenes. Although the composer often wrote under the external influence of extra-musical sources, he rarely revealed them. This study examines the musical and extra-musical imagery which influenced Rachmaninoff's compositional style as observed in op. 39, the most important elements being the Dies irae from the Roman Catholic Mass for the Dead, Russian chant, bell sonorities, and paintings by …

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The Epistemic Power Of Metaphor: A Rhetorical Model For Homiletics., Rodney Kennedy Jan 1990

The Epistemic Power Of Metaphor: A Rhetorical Model For Homiletics., Rodney Kennedy

LSU Historical Dissertations and Theses

This study analyzes the symbiotic relationship between rhetoric and homiletics. The proposed interface between the two disciplines is metaphor. Contemporary research on metaphor in philosophy, rhetoric, sociology, and theology is employed to produce a rhetorical/metaphorical homiletics. A deconstruction of classical homiletics traces the basic preaching model to a Cartesian philosophical starting point. The nature of the Christian scriptures as metaphorical and of Christian liturgy as symbolic is alien to the rational, objective homiletics. An examination of Christian worship as a rhetorical event includes the elements of the theory of rhetoric developed by Michel Foucault: discursive practices, rules, roles, knowledge, and …

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Functionality And Binding Of Washed Mechanically Separated Beef In Restructured Meats., Kyung Chul Koh Jan 1990

Functionality And Binding Of Washed Mechanically Separated Beef In Restructured Meats., Kyung Chul Koh

LSU Historical Dissertations and Theses

Binding and texture are important attributes of restructured meats which are dependent upon protein properties. Meat was pre-salted with 0, 2.25, 4.5, 6.75, or 9.0% sodium chloride (NaCl) and extracted with buffers (pH 6.0) containing 0, 0.6, 1.2, 1.8, or 2.4 M NaCl to determine total extractable protein (TEP). Increased NaCl level in extraction buffers increased TEP, but NaCl levels of 2.25 and 4.5% in meat interfered with release of solubilized proteins into extraction solutions. Restructured beef roasts of 0, 0.45 or 0.9% NaCl and 0, 0.225 or 0.45% sodium tripolyphosphate (STPP) were manufactured with 10% mechanically separated beef (MSB), …

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Genetic Comparisons And Systematic Studies Of Termites (Isoptera)., Amy Kathryn Korman Jan 1990

Genetic Comparisons And Systematic Studies Of Termites (Isoptera)., Amy Kathryn Korman

LSU Historical Dissertations and Theses

Eusociality has evolved in only two insect orders: the Isoptera and Hymenoptera. While hymenopteran genetics has been the subject of intensive study, genetic information on termites is conspicuously lacking. The purpose of this dissertation was to utilize starch gel electrophoresis in genetic studies of termites. Chapter I consists of electrophoretic methods and a study of genetic variability among four families of termites. Although some representative species/colonies demonstrated low levels of variation, the ranges of polymorphic loci and gene diversity were within levels generally observed for the class Insecta. Levels of genetic variation exhibited by termites were higher than those values …

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Structural And Biosynthetic Studies Of Natural Products Of The Asteraceae And Lamiaceae., Marios Andrea Menelaou Jan 1990

Structural And Biosynthetic Studies Of Natural Products Of The Asteraceae And Lamiaceae., Marios Andrea Menelaou

LSU Historical Dissertations and Theses

As part of the investigation of the allelopathic interactions of members of the Florida scrub community, the chemical constituents of Solidago pauciflosculosa (Asteraceae) and Calamintha ashei (Lamiaceae) were studied. Aqueous and organic extracts of fresh leaves of S. pauciflosculosa provided large amounts of diterpene acids. The two major diterpenes isolated, 17-oxygrindelic acid and 17-oxogrindelic acid, showed significant inhibitory effects on germination and radicle growth of two Florida sandhill grasses, Schizachyrium scoparium and Leptochloa dubia. The organic extracts of S. pauciflosculosa were very rich in sesquiterpenes, the three major sesquiterpenes being (+)-epicurlone, (+)-episesquiphellandrene ($-$)-a-trans-bergamotene. These three compounds did not show any …

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Intrinsic Intertextuality:A Methodology For Analyzing The Seamless Intertext., Karen Sue Mitchell Jan 1990

Intrinsic Intertextuality:A Methodology For Analyzing The Seamless Intertext., Karen Sue Mitchell

LSU Historical Dissertations and Theses

This study argues for a methodology that applies contemporary theories of literature and performance to a certain kind of performance script I call a seamless intertext. Working deductively from theory to dramatic text, I explore what selected portions of extant performance and textual theory have to offer in examining, describing, and explaining these seamless intertexts. Working inductively from dramatic text to theory, I extend and offer further clarification and an extension of current theory through a more detailed explanation of the scripting explicit in each dramatic text. In the study I synthesize existing theory in intertextuality and define and describe …

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The Socioeconomic Aspects Of Beef Cattle Production In Louisiana., Emmanuel Kagaba Nzabanita Jan 1990

The Socioeconomic Aspects Of Beef Cattle Production In Louisiana., Emmanuel Kagaba Nzabanita

LSU Historical Dissertations and Theses

This study was divided into: (1) a descriptive study of the farm resources, management practices, veterinary services utilization, and socio-psychological characteristics of Louisiana ranchers in relation to beef cattle performance, (b) a classification of the ranchers according to their utilization of veterinary services with the objective of identifying producer characteristics that are associated with frequent, moderate, and non-use of veterinary services, and (c) identification of factors associated with continuing or ending beef cattle production. The intensity of management, herd health and veterinary services utilization was quantified by scoring and ranking indicator variables that defined these composite variables. Most ranchers had …

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A Study Of Six Selected Coloratura Soprano "Mad Scenes" In Nineteenth Century Opera., Charlotte Fakier Pipes Jan 1990

A Study Of Six Selected Coloratura Soprano "Mad Scenes" In Nineteenth Century Opera., Charlotte Fakier Pipes

LSU Historical Dissertations and Theses

The coloratura "mad scene" was an outstanding feature found in several nineteenth-century operas. Significant in its display of the performer's talent, it requires the ultimate combination of vocal virtuosity and dramatic expression. Each scene exhibits the numerous individual musical characteristics of its specific composer. This study will seek to define and illustrate some of these characteristics as found in the following six scenes: (1) "Al dolce guidami," Anna Bolena (1830), Gaetano Donizetti (1797-1848); (2) "Ah! Non credea mirarti," La Sonnambula (1831), Vincenzo Bellini (1801-1835). (3) "Qui la voce," I Puritani (1835), Bellini. (4) "Argon gl'incensi," Lucia di Lammermoor (1835), Donizetti. …

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Military And Civilian Regimes In Sub-Saharan Africa: A Comparative Analysis Of Public Policy Outputs And Outcomes., Iren Omo-Bare Jan 1990

Military And Civilian Regimes In Sub-Saharan Africa: A Comparative Analysis Of Public Policy Outputs And Outcomes., Iren Omo-Bare

LSU Historical Dissertations and Theses

The principal concern of this study is to assess the influence of military and civilian regimes on public policy in sub-Saharan Africa. The key question underlying this research is: Does it make any difference for a country to be governed by a military or civilian government? Some research indicate that regime type does have policy implications, while others suggest that it does not. To determine the linkage (if any) between regime type and public policy four general hypothesis concerning regime effect on public policy are articulated. There are: (H$\sb1$) Defense expenditure should be higher in countries where the military controls …

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The Spectroscopy Of Vapor Phase Benzaldehyde And Distant Intercellular Interactions Of Chick Embryo Fibroblast Cell Cultures., Vestel Bryan Shirley Jan 1990

The Spectroscopy Of Vapor Phase Benzaldehyde And Distant Intercellular Interactions Of Chick Embryo Fibroblast Cell Cultures., Vestel Bryan Shirley

LSU Historical Dissertations and Theses

Spectra in different regions of the electromagnetic spectrum were taken at different temperatures for benzaldehyde vapor. A review of the literature revealed that the existing data could not be interpreted by this model. Possible perturbations were reviewed. Potential models based on these perturbations were proposed. Calculations were carried out to test the interpretation. No disagreement between experimental and computational findings resulted. The models proposed contradicted no existing experimental determination of the ground state of vapor phase benzaldehyde. It was determined that electron and neutron diffraction experiments were necessary to determine the ground state structure of benzaldehyde. If the results show …

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Soil- And Water-Based Management Strategies For Revegetation And Productivity Improvement Of Brackish Marsh Soil., Gilbert C. Sigua Jan 1990

Soil- And Water-Based Management Strategies For Revegetation And Productivity Improvement Of Brackish Marsh Soil., Gilbert C. Sigua

LSU Historical Dissertations and Theses

Laboratory, greenhouse, and field experiments were conducted on brackish marsh soil of Hackberry, Louisiana (LA). This study was aimed to obtain detailed information on some soil- and water-based management factors that were applicable to the revegetation and productivity improvement of the area. This area was inundated by brackish-saline water, and is now open water, almost totally void of vegetation. The deteriorating productivity and continuous loss of vegetation in the study area can be related to the seasonal and temporal biochemical transformations. These transformations were significantly correlated to precipitation and minimum and maximum temperature in the area. Stochastic regression models were …

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The Uneasiest State: Art, Culture, And Society In New Deal Louisiana, 1933-1943. (Volumes I And Ii)., Richard B. Megraw Jan 1990

The Uneasiest State: Art, Culture, And Society In New Deal Louisiana, 1933-1943. (Volumes I And Ii)., Richard B. Megraw

LSU Historical Dissertations and Theses

During the Great Depression artists working in programs funded by the federal government roamed the nation wielding brushes, jotting notes, and pointing cameras in an attempt to define and characterize American society. Never before and not since has this country conducted so intensive a survey of itself, or one so controversial. Federal patronage of the arts occurred during an anxious period of political and cultural turmoil, a turmoil inherent in the story of the Arts Projects themselves. The very structure, organization, composition, execution, and objectives of the arts agencies mirror the tensions of the age. The artists' selection or avoidance …

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Historic Changes In Channel Morphology Of Mississippi River Tributaries: Southwestern Mississippi., Elaine Grace Yodis Jan 1990

Historic Changes In Channel Morphology Of Mississippi River Tributaries: Southwestern Mississippi., Elaine Grace Yodis

LSU Historical Dissertations and Theses

This study assesses the geomorphological changes to the fluvial systems of two rivers in southwestern Mississippi that have been foreshortened. Channel foreshortening in the lower reaches of these rivers is similar to a lowering of base level and causes a steepening of the channel gradient which leads to channel incision, bank erosion and increased sediment load. Analysis of historical and modern data and a comparison with three unmodified rivers in the same physiographic region, provide an estimate of the magnitude and rate that such disturbances are transmitted through the fluvial system. Degradation and channel instability of the Homochitto River and …

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Role Of Polyamines In Dna Synthesis Of Catharanthus Roseus Cells Grown In Suspension Culture, Rakesh Minocha, Subhash C. Minocha, Atsushi Komamine, Walter C. Shortle Jan 1990

Role Of Polyamines In Dna Synthesis Of Catharanthus Roseus Cells Grown In Suspension Culture, Rakesh Minocha, Subhash C. Minocha, Atsushi Komamine, Walter C. Shortle

Faculty Publications

The requirement for polyamines in the proliferation of cells was first demonstrated in bacteria (3). While significant progress has been made in this field using animal cell cultures, only preliminary studies have been reported with plant tissues. Serafini-Fracassini et al. (9) showed a marked increase in polyamine synthesis early during the G 1 phase, concomitant with the synthesis of RNA, following the break of dormancy in Helianthus tuberosus tuber tissue. A second phase of polyamine accumulation began during the progression of S phase. Torrigiani et al. (10) and Phillips et al. (7) later showed that all major polyamines peaked during …

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Influence Of Storage Temperature And Duration On Deterioration Of Film-Wrapped And Non-Wrapped Mustard, Brassica Juncea Coss., Regina Poillion Bracy Jan 1990

Influence Of Storage Temperature And Duration On Deterioration Of Film-Wrapped And Non-Wrapped Mustard, Brassica Juncea Coss., Regina Poillion Bracy

LSU Historical Dissertations and Theses

Mustard "greens' is a popular fresh vegetable, especially in the South. Fresh market production, however, is restricted to local sales or short-distance markets due to the relatively short shelf life of mustard. Packaging has been shown to successfully extend the shelf life of several fruits and vegetables. To determine the effect of packaging and storage temperature on the postharvest life and quality of mustard, mustard was stored at 1, 4, and 15C in perforated polyethylene bags, Cryovac D-955 60-gauge or 100-guage heat-shrinkable films or not-wrapped. A preliminary experiment was conducted with spinach to develop experiment methodology and for comparison of …

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Root Growth, Root Function, And Water Relations Of Shortleaf Pine (Pinus Echinata Mill.) Bare-Root Seedlings Transplanted Into Different Edaphic Environments., John Closs Brissette Jan 1990

Root Growth, Root Function, And Water Relations Of Shortleaf Pine (Pinus Echinata Mill.) Bare-Root Seedlings Transplanted Into Different Edaphic Environments., John Closs Brissette

LSU Historical Dissertations and Theses

Root growth and its effects on water uptake and plant water relations of seedlings during the initial weeks after transplanting were studied. One-year old bare-root shortleaf pine seedlings were put into six different root zone environments defined by the factorial arrangement of two temperatures and three levels of soil water potential. Needle water potential and stomatal conductance were measured 28 days after planting. The next day, root system absorptive capacity was evaluated by forcing water at a constant hydrostatic pressure through detopped seedlings. The projected surface area of old and new roots was then measured. Also, the relative water content …

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A History Of Rudimental Drumming In America From The Revolutionary War To The Present., Eric Alan Chandler Jan 1990

A History Of Rudimental Drumming In America From The Revolutionary War To The Present., Eric Alan Chandler

LSU Historical Dissertations and Theses

Rudimental drumming gained significance in America during the period of the Revolution. Ever since the late eighteenth-century and through the nineteenth-century, it was used exclusively in the military. This study traces the migration of drum rudiments and their use in military settings from Great Britain to America. The contributions of the Swiss drummers and the incorporation of their drum music into American rudimental drumming are also examined. The introductory chapter covers related pertinent and prefatory topics such as a definition of rudimental drumming, the duties of the military drummer, non-rudimental types of drumming and a summary of the origin and …

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Palynological And Carbon-Isotopic Techniques For Reconstruction Of Paleomarsh Salinity Zones., Gail Lois Chmura Jan 1990

Palynological And Carbon-Isotopic Techniques For Reconstruction Of Paleomarsh Salinity Zones., Gail Lois Chmura

LSU Historical Dissertations and Theses

Palynological and carbon-13 analyses were studied to determine their practicality as tools for paleoecological reconstruction of marsh vegetation communities of the Mississippi delta plain. Both were calibrated on marsh surface sediment samples from four vegetation zones within Barataria Basin, Louisiana: fresh, intermediate, brackish and salt marsh. Samples were taken concurrent to vegetation sampling to allow comparison of sediment data to plant biomass and clip plot data from each of the four zones. The $\partial\sp{13}$C of sedimentary carbon reflects the proportion of C-3 and C-4 species at a site (which corresponds to a salinity gradient in the basin). The average from …

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The Dynamical Behavior Of Rodlike Polymers In Concentrated Solutions., Larry Mark Delong Jan 1990

The Dynamical Behavior Of Rodlike Polymers In Concentrated Solutions., Larry Mark Delong

LSU Historical Dissertations and Theses

In chapter One, zero angle depolarized light scattering methods for particle size determinations are demonstrated by a study on aqueous colloidal suspensions of titanium dioxide. Previous results on a poly(tetrafluoroethylene) latex suspension are also briefly recounted and updated to include reanalysis by an additional independent Laplace inversion method, Provencher's CONTIN. Size distributions may be obtained by Laplace inversion of the correlation functions, with excellent agreement among the various Laplace inversion algorithms. Resolution is greatly enhanced, since rotational motions, which are more sensitive to size than translational motions, are detected at zero angle. In Chapter Two, combined static and quasielastic light …

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Estimation Of Additive And Heterotic Direct And Maternal Genetic Effects For Carcass Traits In Beef Steers., Sidney Marc Derouen Jan 1990

Estimation Of Additive And Heterotic Direct And Maternal Genetic Effects For Carcass Traits In Beef Steers., Sidney Marc Derouen

LSU Historical Dissertations and Theses

Carcass measurements were taken on straightbred and crossbred steers to estimate least squares means and heterosis (1,494 steers) and, to partition additive and heterotic genetic effects (1,536 steers) on hot carcass weight (HCWT), retail yield (YIELD), ribeye area (REA), fat thickness (FT), marbling score (MS) and Warner-Bratzler shear (WBS). Steers were produced over four generations in a rotational crossbreeding study and consisted of Angus (A), Brahman (B), Charolais (C) and Hereford (H) breeds. Two-, three- and four-breed rotation systems were generated with the restriction that each breed combination include the B. Straightbreds were maintained as controls. Treatment, mating system and …

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Seasonal And Daily Variations In Plasma Hormone Concentrations Of The Gulf Killifish, Fundulus Grandis., Arnil Cabading Emata Jan 1990

Seasonal And Daily Variations In Plasma Hormone Concentrations Of The Gulf Killifish, Fundulus Grandis., Arnil Cabading Emata

LSU Historical Dissertations and Theses

Circadian rhythms of hormone secretion and responsiveness to hormones were examined in the gulf killifish. The findings provide additional information to support the hypothesis that reproductive, metabolic and behavioral activities are regulated in part by a temporal interaction of circadian rhythms. These findings include: (1) Daily injections of drugs that influence serotonergic (5-hydroxytryptophan, 5-HTP) and dopaminergic (dihydroxyphenylalanine, DOPA) activities induce conditions appropriate to either summer or winter, and can determine the manner in which a fish reacts reproductively and metabolically to water temperature, the main environmental determinant. (2) Tryptophan-enriched diets stimulated increases in plasma triiodothyronine and somatomedin-C levels, dramatically stimulated …

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Late Quaternary Foraminifera Of The Northwestern Gulf Of Mexico. (Volumes I And Ii)., Richard Allen Denne Jan 1990

Late Quaternary Foraminifera Of The Northwestern Gulf Of Mexico. (Volumes I And Ii)., Richard Allen Denne

LSU Historical Dissertations and Theses

A study of distribution patterns of benthic foraminifera from the Recent and late Pleistocene northwestern gulf of Mexico revealed a close relationship between assemblages and water masses. Multivariate analyses (cluster and factor) of species-frequency data from 120 core tops (87-1361 m) show that the assemblages are associated with the Surface Mixed Layer, Gulf Water, Oxygen Minimum Water, Subantarctic Intermediate Water, Caribbean Midwater, and the Mississippi River outflow. A similar study of 61 samples (283-1341 m) from the last glacial (15,000 yBP) delineated the boundaries of the late Pleistocene bathyal water masses. These were (in estimated paleodepths) the Subtropical Underwater (100?-350 …

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